1. Field of the Invention
Embodiments of the present invention relate generally to digital media and, more specifically, to streaming media effects using audio data and video data.
2. Description of the Related Art
Digital media content distribution systems conventionally include a content server, a content player, and a communications network connecting the content server to the content player. The content server is configured to store digital media content files, which can be downloaded from the content server to the content player. Each digital media content file corresponds to a specific identifying title, such as “Gone with the Wind,” which is familiar to a user. The digital media content file typically includes sequential content data, organized according to playback chronology, and may comprise audio data, video data, or a combination thereof.
The content player is configured to download and play a digital media content file, in response to a user request selecting the title for playback. The process of playing the digital media content file includes decoding audio and video data into a synchronized audio signal and video signal, which may drive a display system having a speaker subsystem and a video subsystem. Playback typically involves a technique known in the art as “streaming,” whereby the content server sequentially transmits the digital media content file to the content player, and the content player plays the digital media content file while content data is received that comprises the digital media content file. To account for variable latency and bandwidth within the communications network, a content buffer queues the incoming content data ahead of the content data actually being played. During moments of network congestion, which leads to lower available bandwidth, less content data is added to the content buffer, which may drain down as content data is being de-queued to support playback at a certain playback bit rate. However, during moments of high network bandwidth, the content buffer is replenished and additional buffer time is added until the content buffer is generally full again. In practical systems, the content buffer may queue content data corresponding to a time span ranging from seconds to more than a minute.
Each digital media content file stored on the content server typically includes video data that is processed before being output for display. The processing may include decoding the video data to raw frames of PCM streams. The processed video data is then output for display. In contrast, the audio data is passed from the content server to an output device, e.g., speakers, without modification. Consequently, playback volume is entirely controlled by a volume setting for the output device and the decoded audio signal is modulated using simple calculations based on the volume setting.
For some digital media content, a preview clip may be designated corresponding to a pivotal moment in a movie. In some cases, the audio data is very loud, e.g., a battle scene, and the output volume control of the content player may also be set at a high level based on the previous content playback. When playback of the preview clip starts, the resulting output volume level of the audio signal may be unpleasantly high. Because the audio data is passed form the content server to the content player without modification, it is not possible to decrease the volume level by modulating the audio data before the audio data is provided to the content player.
As the foregoing illustrates, what is needed in the art is an ability to modulate the audio data without requiring the viewer to adjust the volume control of the content player.